Kv Rating.
Posted by admin in Electronics on January 28, 2012
3.7 volt battery = 1 cell x 3.7 volts (1S)
7.4 volt battery = 2 cells x 3.7 volts (2S)
11.1 volt battery = 3 cells x 3.7 volts (3S)
14.8 volt battery = 4 cells x 3.7 volts (4S)
18.5 volt battery = 5 cells x 3.7 volts (5S)
22.2 volt battery = 6 cells x 3.7 volts (6S)
29.6 volt battery = 8 cells x 3.7 volts (8S)
37.0 volt battery = 10 cells x 3.7 volts (10S)
44.4 volt battery = 12 cells x 3.7 volts (12S)
520KV RPM/Volt
battery lipo 7.4V
540Kv * 7.4V = 3996 rpms
[12800mAh / 1000] * [1 * 11.1V] / 1W = 142.08 Time
12.8 * 11.1 / 1 = 142.08
Time = [mAh / 1000] * [# of batteries * battery voltage] / device power
Device is rated at 1W using 4 AA [1.5 Volt] batteries rated at 1000mAh.
Time = [ 1000mAh / 1000 ] * [4 * 1.5 Volts] / 1 W = 6 Hours
References:
http://en.wikipedia.org/wiki/Brushless_DC_electric_motor#Kv_rating
xev: know what the “key codes” are.
xev comamnd.
how to change default file manager in firefox/linux.
Try this:
Create 2 new boolean values with these names:
network.protocol-handler.expose.file=FALSE network.protocol-handler.external.file=TRUE
Open Edit -> Preferences -> Applications. In Content file look for “file”-protocol and change it to use thunar.
(you may need to open a local folder for the “file”-protocol to show in the list. ex. file:///home/user)
tested under firefox 9.
Qt 4.8.0 Configure Options for Linux
Posted by admin in Nokia's Qt, Programming on December 24, 2011
Here you will find the complete Configure Parameters on how to configure Nokia’s Qt 4.8.0 for Linux.
youtube – 500 Internal Server Error.
Posted by admin in Uncategorized on December 19, 2011
I was youtubing and i clicked on a malformed video url and this is the message that i got.. hehehe… i find it funny… trained monkeys… lol… i wonder what the cypher is… =)
usb audio multiplexer gui program.
Posted by admin in Electronics on December 13, 2011
Screen Shots:
References:
http://jumperone.com/2011/12/usb-audio-multiplexer
Asterisk CLI: Most common commands.
Posted by admin in Uncategorized on December 3, 2011
localhost*CLI>core restart now
localhost*CLI>core reload
localhost*CLI>sip show registry
localhost*CLI>sip reload
How to use Omron G5V-1 relay.
Posted by admin in Electronics on November 19, 2011
How to use a SPDT Relay.
Read the rest of this entry »
How to compress/tar a directory.
Posted by admin in Uncategorized on November 17, 2011
lets say that we want to backup everything inside schoolproject directory:
/home/schoolproject/index.php
/home/schoolproject/thesisdoc.odt
/home/schoolproject/images/logo.png
to compress:
tar -pczf backup.tar.gz /home/websites/ tar -jcvf backup.tar.bz2 /home/websites/
result will be a backup.tar.gz with all your files.
to extract:
tar -xzjf backup.tar.gz tar -xvjf backup.tar.bz2
this will recreate schoolproject directory with all its files and sub-directories.
Making Sony A100 Time Lapse Capable.
Posted by admin in Uncategorized on November 17, 2011
If you been keeping up with my blog you will know that I tried to get my Sony DSLR-A100 to do time lapse using PTP mode under gphoto2 and this wasn’t possible… you can read more about it in my previous post according to the developers in gphoto mailing list, this camera doesnt support time lapse capability despite the camera having PTP functionality. So after all my research and time wasted trying to get my camera to work in time-lapse mode and not being successful I decided to create my own time lapse device and this is how I did it.
ClusterMap
